mirror of https://github.com/serai-dex/serai.git synced 2024-09-29 18:01:05 +00:00

History

Luke Parker 5b3c9bf5d0 DKG Blame (#196 ) * Standardize the DLEq serialization function naming They mismatched from the rest of the project. This commit is technically incomplete as it doesn't update the dkg crate. * Rewrite DKG encryption to enable per-message decryption without side effects This isn't technically true as I already know a break in this which I'll correct for shortly. Does update documentation to explain the new scheme. Required for blame. * Add a verifiable system for blame during the FROST DKG Previously, if sent an invalid key share, the participant would realize that and could accuse the sender. Without further evidence, either the accuser or the accused could be guilty. Now, the accuser has a proof the accused is in the wrong. Reworks KeyMachine to return BlameMachine. This explicitly acknowledges how locally complete keys still need group acknowledgement before the protocol can be complete and provides a way for others to verify blame, even after a locally successful run. If any blame is cast, the protocol is no longer considered complete-able (instead aborting). Further accusations of blame can still be handled however. Updates documentation on network behavior. Also starts to remove "OnDrop". We now use Zeroizing for anything which should be zeroized on drop. This is a lot more piece-meal and reduces clones. * Tweak Zeroizing and Debug impls Expands Zeroizing to be more comprehensive. Also updates Zeroizing<CachedPreprocess([u8; 32])> to CachedPreprocess(Zeroizing<[u8; 32]>) so zeroizing is the first thing done and last step before exposing the copy-able [u8; 32]. Removes private keys from Debug. * Fix a bug where adversaries could claim to be using another user's encryption keys to learn their messages Mentioned a few commits ago, now fixed. This wouldn't have affected Serai, which aborts on failure, nor any DKG currently supported. It's just about ensuring the DKG encryption is robust and proper. * Finish moving dleq from ser/deser to write/read * Add tests for dkg blame * Add a FROST test for invalid signature shares * Batch verify encrypted messages' ephemeral keys' PoP		2023-01-01 01:54:18 -05:00
..
src	DKG Blame (#196 )	2023-01-01 01:54:18 -05:00
Cargo.toml	Have Transcript::append_message take in AsRef<[u8]>, not &[u8]	2022-11-05 18:43:36 -04:00
LICENSE	Transcript crate with both a merlin backend and a basic label len value backend	2022-05-03 07:20:24 -04:00
README.md	Document the transcript library	2022-07-09 00:37:39 -04:00

README.md

Flexible Transcript

Flexible Transcript is a crate offering:

Transcript, a trait offering functions transcripts should implement.
DigestTranscript, a competent transcript format instantiated against a provided hash function.
MerlinTranscript, a wrapper of merlin into the trait (available via the merlin feature).
RecommendedTranscript, a transcript recommended for usage in applications. Currently, this is DigestTranscript<Blake2b512> (available via the recommended feature).

The trait was created while working on an IETF draft which defined an incredibly simple transcript format. Extensions of the protocol would quickly require a more competent format, yet implementing the one specified was mandatory to meet the specification. Accordingly, the library implementing the draft defined an IetfTranscript, dropping labels and not allowing successive challenges, yet thanks to the trait, allowed protocols building on top to provide their own transcript format as needed.

DigestTranscript takes in any hash function implementing Digest, offering a secure transcript format around it. All items are prefixed by a flag, denoting their type, and their length.

MerlinTranscript was used to justify the API, and if any issues existed with DigestTranscript, enable a fallback. It was also meant as a way to be compatible with existing Rust projects using merlin.